From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- drivers/sbus/char/riowatchdog.c | 293 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 293 insertions(+) create mode 100644 drivers/sbus/char/riowatchdog.c (limited to 'drivers/sbus/char/riowatchdog.c') diff --git a/drivers/sbus/char/riowatchdog.c b/drivers/sbus/char/riowatchdog.c new file mode 100644 index 00000000000..d1babff6a53 --- /dev/null +++ b/drivers/sbus/char/riowatchdog.c @@ -0,0 +1,293 @@ +/* $Id: riowatchdog.c,v 1.3.2.2 2002/01/23 18:48:02 davem Exp $ + * riowatchdog.c - driver for hw watchdog inside Super I/O of RIO + * + * Copyright (C) 2001 David S. Miller (davem@redhat.com) + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#include + +/* RIO uses the NatSemi Super I/O power management logical device + * as its' watchdog. + * + * When the watchdog triggers, it asserts a line to the BBC (Boot Bus + * Controller) of the machine. The BBC can only be configured to + * trigger a power-on reset when the signal is asserted. The BBC + * can be configured to ignore the signal entirely as well. + * + * The only Super I/O device register we care about is at index + * 0x05 (WDTO_INDEX) which is the watchdog time-out in minutes (1-255). + * If set to zero, this disables the watchdog. When set, the system + * must periodically (before watchdog expires) clear (set to zero) and + * re-set the watchdog else it will trigger. + * + * There are two other indexed watchdog registers inside this Super I/O + * logical device, but they are unused. The first, at index 0x06 is + * the watchdog control and can be used to make the watchdog timer re-set + * when the PS/2 mouse or serial lines show activity. The second, at + * index 0x07 is merely a sampling of the line from the watchdog to the + * BBC. + * + * The watchdog device generates no interrupts. + */ + +MODULE_AUTHOR("David S. Miller "); +MODULE_DESCRIPTION("Hardware watchdog driver for Sun RIO"); +MODULE_SUPPORTED_DEVICE("watchdog"); +MODULE_LICENSE("GPL"); + +#define RIOWD_NAME "pmc" +#define RIOWD_MINOR 215 + +static DEFINE_SPINLOCK(riowd_lock); + +static void __iomem *bbc_regs; +static void __iomem *riowd_regs; +#define WDTO_INDEX 0x05 + +static int riowd_timeout = 1; /* in minutes */ +module_param(riowd_timeout, int, 0); +MODULE_PARM_DESC(riowd_timeout, "Watchdog timeout in minutes"); + +#if 0 /* Currently unused. */ +static u8 riowd_readreg(int index) +{ + unsigned long flags; + u8 ret; + + spin_lock_irqsave(&riowd_lock, flags); + writeb(index, riowd_regs + 0); + ret = readb(riowd_regs + 1); + spin_unlock_irqrestore(&riowd_lock, flags); + + return ret; +} +#endif + +static void riowd_writereg(u8 val, int index) +{ + unsigned long flags; + + spin_lock_irqsave(&riowd_lock, flags); + writeb(index, riowd_regs + 0); + writeb(val, riowd_regs + 1); + spin_unlock_irqrestore(&riowd_lock, flags); +} + +static void riowd_pingtimer(void) +{ + riowd_writereg(riowd_timeout, WDTO_INDEX); +} + +static void riowd_stoptimer(void) +{ + u8 val; + + riowd_writereg(0, WDTO_INDEX); + + val = readb(bbc_regs + BBC_WDACTION); + val &= ~BBC_WDACTION_RST; + writeb(val, bbc_regs + BBC_WDACTION); +} + +static void riowd_starttimer(void) +{ + u8 val; + + riowd_writereg(riowd_timeout, WDTO_INDEX); + + val = readb(bbc_regs + BBC_WDACTION); + val |= BBC_WDACTION_RST; + writeb(val, bbc_regs + BBC_WDACTION); +} + +static int riowd_open(struct inode *inode, struct file *filp) +{ + nonseekable_open(inode, filp); + return 0; +} + +static int riowd_release(struct inode *inode, struct file *filp) +{ + return 0; +} + +static int riowd_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + static struct watchdog_info info = { + WDIOF_SETTIMEOUT, 0, "Natl. Semiconductor PC97317" + }; + void __user *argp = (void __user *)arg; + unsigned int options; + int new_margin; + + switch (cmd) { + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &info, sizeof(info))) + return -EFAULT; + break; + + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + if (put_user(0, (int __user *)argp)) + return -EFAULT; + break; + + case WDIOC_KEEPALIVE: + riowd_pingtimer(); + break; + + case WDIOC_SETOPTIONS: + if (copy_from_user(&options, argp, sizeof(options))) + return -EFAULT; + + if (options & WDIOS_DISABLECARD) + riowd_stoptimer(); + else if (options & WDIOS_ENABLECARD) + riowd_starttimer(); + else + return -EINVAL; + + break; + + case WDIOC_SETTIMEOUT: + if (get_user(new_margin, (int __user *)argp)) + return -EFAULT; + if ((new_margin < 60) || (new_margin > (255 * 60))) + return -EINVAL; + riowd_timeout = (new_margin + 59) / 60; + riowd_pingtimer(); + /* Fall */ + + case WDIOC_GETTIMEOUT: + return put_user(riowd_timeout * 60, (int __user *)argp); + + default: + return -EINVAL; + }; + + return 0; +} + +static ssize_t riowd_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) +{ + if (count) { + riowd_pingtimer(); + return 1; + } + + return 0; +} + +static struct file_operations riowd_fops = { + .owner = THIS_MODULE, + .ioctl = riowd_ioctl, + .open = riowd_open, + .write = riowd_write, + .release = riowd_release, +}; + +static struct miscdevice riowd_miscdev = { RIOWD_MINOR, RIOWD_NAME, &riowd_fops }; + +static int __init riowd_bbc_init(void) +{ + struct linux_ebus *ebus = NULL; + struct linux_ebus_device *edev = NULL; + u8 val; + + for_each_ebus(ebus) { + for_each_ebusdev(edev, ebus) { + if (!strcmp(edev->prom_name, "bbc")) + goto found_bbc; + } + } + +found_bbc: + if (!edev) + return -ENODEV; + bbc_regs = ioremap(edev->resource[0].start, BBC_REGS_SIZE); + if (!bbc_regs) + return -ENODEV; + + /* Turn it off. */ + val = readb(bbc_regs + BBC_WDACTION); + val &= ~BBC_WDACTION_RST; + writeb(val, bbc_regs + BBC_WDACTION); + + return 0; +} + +static int __init riowd_init(void) +{ + struct linux_ebus *ebus = NULL; + struct linux_ebus_device *edev = NULL; + + for_each_ebus(ebus) { + for_each_ebusdev(edev, ebus) { + if (!strcmp(edev->prom_name, RIOWD_NAME)) + goto ebus_done; + } + } + +ebus_done: + if (!edev) + goto fail; + + riowd_regs = ioremap(edev->resource[0].start, 2); + if (riowd_regs == NULL) { + printk(KERN_ERR "pmc: Cannot map registers.\n"); + return -ENODEV; + } + + if (riowd_bbc_init()) { + printk(KERN_ERR "pmc: Failure initializing BBC config.\n"); + goto fail; + } + + if (misc_register(&riowd_miscdev)) { + printk(KERN_ERR "pmc: Cannot register watchdog misc device.\n"); + goto fail; + } + + printk(KERN_INFO "pmc: Hardware watchdog [%i minutes], " + "regs at %p\n", riowd_timeout, riowd_regs); + + return 0; + +fail: + if (riowd_regs) { + iounmap(riowd_regs); + riowd_regs = NULL; + } + if (bbc_regs) { + iounmap(bbc_regs); + bbc_regs = NULL; + } + return -ENODEV; +} + +static void __exit riowd_cleanup(void) +{ + misc_deregister(&riowd_miscdev); + iounmap(riowd_regs); + riowd_regs = NULL; + iounmap(bbc_regs); + bbc_regs = NULL; +} + +module_init(riowd_init); +module_exit(riowd_cleanup); -- cgit v1.2.3